Weight transfer producing undesirable results for clothing(2.78c)
I suggested projected face interpolated in the comments, but in your case "nearest face interpolated" works better. The reason is 'projected' projects along faces normals and in your case, some faces normals does not point to the base mesh.



Here is your file back: 

Note:

Often, data transfer has to be tuned, and so you need to retry often. That's why I find easier and quicker to use 'data transfer operator' instead of the modifier.